Lead connector and cap



Patented Apr. 11, 1950 LEAD CONNECTOR AND CAP John H. Thornbery, Whitefish Bay, Wis., assigner to Milwaukee Gas Specialty Company, Milwaukee, Wis., a corporation of Wisconsin Application March 31, 1947, Serial No. 738,455

1 Claim. (Cl. 173-328) This invention relates, in general, to electric switches and has particular relation to an improved form of combined lead connector and capi While the particular device which I shall describe hereinafter in connection with the drawing is a combined electric switch and quick detachable terminal connector for use with a thermoelectric safety shutoff device and its thermocouple leads, it is to be understood that the invention is not limited to such use but may be employed for all similar purposes as suitable or desired.

The combined electric switch and quick detachable terminal connector of the present invention may be characterized as an improvement on the electric switch and terminal connector disclosed and claimed in prior patent of Stanley S. Guelson No. 2,318,775, granted May 11, 1943.

One of the main objects of the present invention is to provide in a switch of the class described quick detachable terminal connector means adapted to provide a quick detachable terminal connection between the lead conductors and the thermoelectric safety shutoff or other device, and a new form of switch at the quick detachable terminal connection for opening or disabling and closing or completing the circuit between the lead conductors and the connected device.

Another object of the invention is to provide a new form of electric switch and terminal connector which is operable to provide an effective manuel release feature whereby the safety shutoff valve of the thermoelectric shutoff device may be closed manually by the simple expedient of jacking the terminal of the thermocouple attaching nut out of contact with the cooperating terminal connected to the coil of the electromagnet of the thermoelectric shutoff device.

Another object of the invention is to provide a new form of electric switch and terminal connector having various features of novelty and advantages, and which is particularly characterized by its simplicity in construction, its relatively few parts, its economy in manufacture and its effectiveness in use.

Another object of the invention is to provide an electric switch and terminal connector comprising a cap having internal splined or keyed engagement with the attaching nut and held against axial movement relative thereto, which cap encloses the terminal means and is adapted to be grasped with the hand and turned to screw the nut into and from a cooperating bushing to move the terminal of the attaching nut. .into and out of contact with its cooperating terminal member.

Further objects and advantages of the invention will be apparent from the following detailed description, taken in connection with the accompanying drawing in which:

Figure l is a longitudinal axial sectional View through a safety shutoff device embodying the electric switch and quick detachable terminal connector of the present invention;

Figure 2 is an enlarged sectional view showing the terminal of the attaching nut out of contact with the cooperating terminal member;

Figure 3 is a fragmentary sectional view taken on the line 3-3 of Figure 1; and

Figure 4 is a fragmentary and more or less diagrammatic view showing the safety shutoff device shown in Figure 1 in a fuel supply system for a main burner and a pilot burner.

Referring to the drawing, the burner shown at I0 in Figure 4 is any suitable or preferred main burner, for example, for an oven, room, or space heater, water heater, floor furnace, oven burner, top burner or any other burner.

The main burner I 0 is supplied with fuel by a pipe II which is connected to the burner through the interior of the safety shutoff valve designated in its entirety at I2. Where the burner I0 is a, gas burner, the fuel supply pipe I l is preferably connected to the burner through a suitable air and gas admixture chamber and fuel delivery nozzle at the burner (not shown), as well understood in the art.

Figure 4 shows a pilot burner i3 in juxtaposition to the main burner I0. The pilot burner I3 is adapted to provide a, pilot light I4 for lighting the main burner.l A fuel supply pipe I 5, connected, for example, to the safety shutoff valve l2 or to the fuel supply line otherwise as desired, supplies gaseous fuel to the pilot burner I3.

The safety shutoff valve l2 is, in general, ofv the type shown in the prior patent of Clarence' and the outlet I8 opens from an outlet cham-l ber 20. A port or passage 2! provides for communication between the inlet chamber I 9 and the outlet vchamber 20. Valve seats 22 and 23 are provided on the .partition 23 through which the port 2| opensyone of these valve seats 22 surrounding one end of the port 2 I, and the other 3 valve seat 23 surrounding the other end of this ort. p The safety shutoff valve or ow controlling member 24 is iixed, for example, by a pin 25 upon the inner end of the valve stem 26, preferably for some relative movement thereon. so as to have self-accommodating seating engagement with the cooperating valve seat 22. The valve member 24 `is preferably provided with a valve gasket or yielding valve facing 21 secured in place jbyr a screw 28, or in any other suitable manner, :and adapted to engage the valve seat 22. when the safety shutoi valve is closed.

-.The valve stem 26 extends outwardly for reciprocatory movement through an opening in the ,-linnerend of a magnet and armature housing 29. The armature 3D isisecured tothe outer end of the valve stem 25 preferably sufficiently loosely to 'permit self-accommodation of the armature to 1 the pole ends of the magnet frame 3|. '25 v.disposed generally -concentrically of the housing 29, and the armature and magnet frame i are .disposed within this housing. The housing F28 nts: telescopically in a cap or hood 32, which, j forexample, is screwed vat 33 vinto the valve body I6 preferably with a sealing gasket 34 therebev tween. A valvespring seating member 35 abuts v the inner end of the 'housing 29, and packing is preferably interposed therebetween at 36. The j valve spring 31' is in the form of a coiled compression. spring interposed between vthe safety The stem shutoir valve member 2liv and the seating member 35.

The magnetframe 3l is ysecured to a terminal bushing 38. The shank .of the bushing 33 extends through an opening in the outer end of the lcap 32 and is externally threaded for threaded engagement with a nut 39 by means of which the bushing ,38' is clamped to the outer end of thecap 32. A sealing gasket 4B is preferably interposed between the headed inner end ofthe bushing 38 and the outer end of the -cap 32. The outer endof the housing 29 is peened, for example, Vat 4l over the .anged or headed innerend of the bushing 38.

In the illustrated embodiment of the invention a thermocouple, indicated at 42, is positioned so that the hot junction 43 thereof will be heated by the lpilot name |4as long as the pilot flame is burning, The thermoeouple and leads therefor selected for illustration may be similar to the Athermocouple and leads more fully disclosed in Oscar J. Leins Patent No. 2,126,564, patented August l9, 1938, or the thermocouple and leads may he of any other vsuitable or preferred form.

For the purposev of the present description, sufce it to state that the particular thermocouple selected for illustration comprises an outer tubular metallic thermocouple Velement and an inner metallic thermocouple element of different thermoelectric characteristics. The inner thermocouple element is joined at one end to the outer end of the outer thermocouple element to form the thermoj-unction 43 which is placed in position to be heated by the pilot ame i4. An inner lead conductor 44 is joined to the inner thermocouple element to form an internal thermojunction, and an outer tubular lead conductor- 45 surrounds the inner llead conductor and is connected to the outer thermocouple element, for example, through a sleeve 45 to form a third thermojunction. Theinner leadconductor 44 is insulated from the outer lead conductor 45, for example, by a wrapping of insulation 41 on the inner lead conductor.

.connector sleeve 52 and bushing 38.

A quick detachable or removable connection and manual release feature are provided between the electromagnet of the safety shutoi device and the ends of the leads 44 and 45 opposite the ends 'which are connected to the thermocouple elements. To this end the inner lead conductor l44 is provided with a connector or terminal cone 5D. as shown in Figure l. The cone 5! seats in a-correspondingly recessed outer end of a terminal tip 5| and is clamped in contact therewith by a connector sleeve 52. The adjacent end of the outer tubular lead conductor i5 is connected in circuit with one side of the coil 53 through the The other side of the coil 53 is connected to the terminal tip 5I, the parts being suitably insulated as shown. The. coil 53 is wound around the legs of the magnet frame 3| which, with the coil 53, constitutes the electromagnet of the device shown in the drawings.

The cap 54 vhas an annular flange 55 which surrounds the terminal connection and the adiacentend ci the cap 32. The outer end of the cap 54 is of reduced diameter at 55,5 and has internal splined or keyed engagement at 51 with the outer end of the connector sleeve 52 which is screwed into the outer end of the bushing 38. The end of the outer tubular lead conductor 45 is lpeened over the inner end of the connector sleeve 52 and insulated from the connector cone 5! by .insulation at 5t. The outer end of the reduced diameter part 56 of the cap 5d has an end wall vor ange 59 provided with an axial opening through which the lead conductors' extend. The end wall or flange 5S is Xed between `the outer end of the connector sleeve 52 and a collar Aor abutment member Se fixed on the vtubular lead conductor.

For the purpose of resetting the valve 24 to open position and the armature 3i! to attracted position, reset stem 55 is mounted for reciprocatory movement axially in a closure member 3E. The :member 5E is screwed into an opening 61 extending from kthe interior of lthe valve body i5 in alignment with the port 2i and valve 2Q. A reset button `68 is secured to the outer end of the stem `65, for example, by a pin 59. The button 68 hassliding movement in an opening 'it in the member 65 The inner end of they stem 5 is headed and has a valve or annular rib 1i thereon which cooperates with a leather or other suitable washer 12 to seal the valve body against leakage along the reset stem S5 when the stem is in retracted position. The valve li and washer i2' are shown as a precaution in the event the bellows or daphragm, 'to be presently described, is ruptured. In actual practice the valve 1I and washer 'l2 may be omitted, and the device thereby further simplified.

The flexible bellows or bellows-like or diaphragm member "l5 is formed of rubber, rubberlike or other suitable material. rEhe bellows 'l5y is clamped peripherally at 16 between the valve body l5 and the closure member 65 and forms an impervious covering over the inner end of the closure member i6-and the inner end of the reset stem 65, thus sealing the valve body against leakagev vavzljaoent to the closure member 5.5 and the stem 55.. The nexible bellows 15 is'shown of reduced diameterv at its inner end at 11 to enterthe port 2l, asshown in Figure l when the reset stem 55 is moved inwardly to-.resetting' position. Inv resetting position of the stem 65;

the enlarged diameter outer portion of the bel-l` lows 15 cooperates or seats annularlyon the valve seat 23, thus shutting off the supply of fuel to the main burner during the resetting operation. The reduced diameter and enlarged diameter portions of the bellows I5 may be of corrugated form as shown in the drawings, or of other suitable form.

In the illustrated embodiment of the invention the pipe I5 for supplying fuel to the pilot burner I3 is connected through a port I8 with the interior of the valve body I6 between the valve seats 22 and 23. The pilot burner I3 thus receives fuel whenever the shutoff valve 24 is open and regardless of whether the flow interrupter valve formed by the bellows 15 is open or closed. This may, of course, vary widely in so far as the present invention is concerned.

The portion of the bellows 15 which extends over the inner end of the reset stem 65 is secured, for example, by vuloanizing to a serrated surface 'I9 on the inner end of the stern 65. The reset stem 65 and button 68 are moved to retracted or outwardly projecting position following a resetting operation by a coiled spring 80 which is shown encircling' the stem 65 and interposed between the button 68 and an internal annular flange or abutment 8| on the closure member 65.

The annular and outwardly directed surface 82 formed on the cap 54 between the reduced and enlarged diameter portions thereof may be provided with on and olf markings (not shown) and with arrows showing the direction in which the cap 54 should be turned to open and close the thermoelectric circuit between the thermocouple and the electromagnet. By turning the cap 54 to on position in the direction of the arrow adjacent to the on marking, the connector sleeve 52 is screwed inwardly into the bushing 38 to engage the cone 58 with the terminal tip 5I, thus completing the circuit between the thermocouple and the electromagnet. By turning the cap 54 to off position in the direction of the arrow adjacent to the off marking, the connector sleeve 52 is screwed outwardly from the bushing 38, thus separating the cone 50 from the terminal tip 5I and opening the circuit between the thermocouple and the electromagnet. This provides an effective manual release feature whereby the shutoff valve 24 may be closed by jacking the terminal cone 50 out of contact with the socketed end of the terminal tip 5 I.

In general, the operation of the device is similar to the operation described in the prior patents previously mentioned and, being well understood in the art, will not be described in detail. Suffice it to state that the flexible bellows I5 constitutes a ow interrupter valve which is adapted to be stretched by the resetting operation of the reset stem 65 into enga-gement with the cooperating valve seat 23 to shut olf the now of fuel to the burner during the resetting operation. With the bellows arranged as shown and described it also performs the additional function of sealing the device against leakage of fuel from the valve body I6 adjacent to the reset means. The cap 54, with its keyed or splined engagement with the connector sleeve 52 and its mounting against axial movement relative to the sleeve 52 provides a manual release feature whereby the shutoff valve 24 may be closed manually by merely turning the cap 54, which thereby jacks the terminal cone out of and into contact with the socketed end of the terminal tip 5 I.

The invention is not limited to use with a valve type safety shutoi device as shown in the drawing but may be employed with switch type shutoff devices; also on automatic valves such as those employing a thermopile or other type of thermoelectric generator and elsewhere as suitable and desired.

The embodiments of the invention shown in the drawings, therefore, are for illustrative purposes only, and it is to be expressly understood that the drawing and the accompanying specication are not to be construed as a denition of the limits or scope of the invention, reference being had to the appended claim for that purpose.

I claim:

In a device of the class described, in combination, a terminal bushing having a threaded part, a first terminal member fixed in said bushing and insulated electrically therefrom, a connector member having threaded engagement with the threaded part of said bushing and adapted to be screwed from and toward said bushing, a cap having an end wall in juxtaposition to the adjacent end of said connector member and fixed internally against turning movement relative to said connector member whereby said connector member is turned by turning of said cap, conductor means comprising an outer tubular lead conductor extending axially through the end wall of said cap and axially through said connector member, an inner lead conductor extending through said tubular lead conductor and insulated therefrom, a second terminal member xed on the inner end of said inner conductor beyond the inner end of said outer tubular conductor and in juxtaposition to said rst terminal member, insulation between said second terminal member and the inner end of said connector member and abutting the inner end of said connector member, and an abutment member fixed externally on said outer tubular conductor with said cap, connector member and insulation held against relative vlongitudinal displacement between said abutment member and said second terminal member whereby turning of said cap screws said connector member toward and from said bushing and said second terminal member into and out of contact with said rst terminal member.

JOHN H. THORNBERY.

REFERENCES CITED The following references are of record in the iile of this patent:

UNITED STATES PATENTS Number Name Date 1,103,533 Nilsson July 14, 1914 1,989,752 Ice Feb. 25, 1935 2,164,017 Lavarack et al. June 27, 1939 2,318,775 Guelson May 11, 1943 2,318,822 Wantz May 11, 1943 2,340,234 Thornbery et al. Jan. 25, 1944 2,345,276 McCarty Mar. 28, 1944 

